Mert Yıldız - Academia.edu (original) (raw)

Papers by Mert Yıldız

Mustafa Kemal Üniversitesi tarım bilimleri dergisi, Apr 19, 2021

Kombu tea is a slightly sweet and acidic beverage that is consumed worldwide but has a low level ... more Kombu tea is a slightly sweet and acidic beverage that is consumed worldwide but has a low level of awareness in our country, resulting from the symbiotic relationship between acetic acid fermentation and alcohol fermentation. Temperature is an important parameter in the production conditions of this drink, which has many health benefits. This study aimed to determine the effect of incubation temperature and fermentation time on physicochemical and microbiological properties of kombucha tea. Methods and Results: In this study, physicochemical and microbiological changes on days 0, 5, 10 and 15 th occurring as a result of incubation in room conditions (15-20°C) and incubator conditions (28°C) were investigated. The pH of the Kombu tea samples produced at room temperature is 3.51-5.39; brix values 8.71-9.57; alcohol content 1.10-3.07%; total amount of phenolic substance 374-364 mg gallic acid L-1 ; antioxidant activity was determined as 80.57-76.58% and density value was 1.037-1.036 g mL-1. The pH of the Kombu tea samples fermented at 28 °C is 3.22-5.39; brix 8.71-10.10; alcohol content 1.10-3.76%; the total amount of phenolic substance 374-430 mg gallic acid L-1 ; antioxidant activity was determined to be 80,57-80,00% and density was 1.037-1.035 g mL-1. A statistically significant difference (p <0.05) in the a* and b* values on the 5 th and 10 th days of different fermentation conditions and the L* and a* values on the 15 th day has been determined. An increase in the number of microorganisms (p <0.05) was detected depending on the fermentation days at both of the Kombu tea produced at different temperatures. According to the fermentation conditions at different temperatures, the increase in the number of yeast-mold was statistically insignificant, while the increase in the 5 th and 10 th days was statistically significant (p <0.05) in terms of the number of bacteria. Conclusions: Instead of standardizing the fermentation temperature and/or duration, the pH value of the product is considered to be an important criterion in determining the fermentation conditions in the production of Kombu tea. Significance and Impact of the Study: In the light of these findings, if standardization is necessary, fermentation time at 28°C is recommended to be 10 days, or at room temperature 15 days.

Companion Publication of the 2019 on Designing Interactive Systems Conference 2019 Companion

Food is an essential nutritional source for all humans, yet tons of food is wasted at an increasi... more Food is an essential nutritional source for all humans, yet tons of food is wasted at an increasing rate each year. Although previous HCI studies examined this issue, most of this work focuses on the domestic context. To the best of our knowledge, no study explored the food waste in the hospitality sector from a design perspective. Addressing this gap, we made observations and interviews in a high-end hotel restaurant kitchen to better understand the sources of food waste in restaurants. From our findings, we envisioned three design speculations which can inspire HCI researchers and practitioners explore this issue further.

Theoretical and Applied Forestry, Sep 1, 2022

Yapay olarak tesis edilen, tohum bahçeleri ve doğal ormanlardan tescillenen tohum meşcereleri; di... more Yapay olarak tesis edilen, tohum bahçeleri ve doğal ormanlardan tescillenen tohum meşcereleri; diğer fonksiyonları yanında ormancılık uygulamalarının en önemli tohum kaynaklarıdır. Ülkemiz ormancılığında bu amaçla 12 tür ve 1443.3 hektarda 185 tohum bahçesi ile 32 tür ve 41880.1 hektarda 318 tohum meşceresi tescillenmiştir. Bu tohum kaynakları içerisinde, doğal yayılış alanının büyüklüğüne bağlı olarak Kızılçam (Pinus brutia Ten.) tohum bahçeleri (78 adet, 663.2 ha) ve tohum meşcereleri (72 adet, 10421.9 ha) bakımından en yüksek paya sahiptir. Tohum kaynaklarının tescil ve tesisine katkı sağlanması amacıyla gerçekleştirilen derleme niteliğindeki bu makalede, Orman Ağaçları ve Tohumları Islah Araştırma Enstitüsü Müdürlüğü tarafından yayımlanan güncel veriler ışığında tohum bahçeleri ve tohum meşcereleri irdelenmiştir.

2020 Medical Technologies Congress (TIPTEKNO), 2020

In this study, the application of Q-routing method to the diffusion MR fiber tractography problem... more In this study, the application of Q-routing method to the diffusion MR fiber tractography problem is proposed. In this way, while benefiting from the advantages of the local streamline methods, to obtain the robustness of global methods by considering the total cost of the path instead of local orientations is aimed. The proposed Q-routing based method, is evaluated on the FiberCup phantom, which is a diffusion phantom mimicing the fiber connections of the human cerebral white matter. The results reveal the potential of the proposed method on the diffusion MR fiber tractography problem.

Lecture Notes in Mechanical Engineering, 2019

Izmir based Information Technology (IT) solution provider develops supply chain management softwa... more Izmir based Information Technology (IT) solution provider develops supply chain management software tools for many customers from fast moving consumer goods sector (FMCG). Customers of the FMCG sector needs to be visited a certain number of times in a given period by sales representatives. The company must decide which customers must be visited in which sequence by each sales representative while obeying visit frequency and time windows requirements. These decisions have significant impact on total cost. For this reason, finding an optimal route for every sales representative for each day of the planning horizon is important. This practically challenging and technically important problem can be described as periodic multiple depot traveling salesman problem with time windows (PMDTSPTW). We propose a novel mathematical model for the optimal solution of this problem. The proposed model minimizes the total distance traveled by sales representatives by deciding which sales representative will visit which customer on which day while following the time windows to collect demand data. The proposed model is applicable to any company from FMCG sector. The solution approach in this study is implemented and tested with real life including coordinates and location data of customers and sales representatives from Turkey’s largest beer distributor. The proposed model is solved using IBM ILOG CPLEX Optimization Studio version 12.8. The results show significant improvement over the current situation. To ensure efficient usage of the proposed approach, a user-friendly decision support system (DSS) is constructed and implemented.

Proceedings of the Design Society, 2021

Taking on the challenge of motivating users to drink water regularly, we designed a smart water b... more Taking on the challenge of motivating users to drink water regularly, we designed a smart water bottle that can track water intake behavior and inform users about this behavior through ambient feedback. We then conducted two studies to explore the bottle's feedback design from the perspective of users and designers. First, we conducted semi-structured interviews with 10 prospective users and found that they would like to receive personalized, precise, gamified and reminding feedback. Second, we conducted a design workshop with 13 professional designers to explore the range of visualizations that can be used to give feedback. Analyzing these visualizations, we identified three reminder types (augmenting, restoring and balancing) and six visualization styles grouped according to three dimensions of ambient displays (representation fidelity, notification level, aesthetic emphasis). In this paper, we first explain our water bottle concept along with existing solutions. Then, we repo...

DS 110: Proceedings of the 23rd International Conference on Engineering and Product Design Education (EPDE 2021), 2021

This paper reports on the procedure and the results of a design activity carried out to reflect o... more This paper reports on the procedure and the results of a design activity carried out to reflect on time and timekeeping practices. The design activity involved a diary study followed by an idea generation workshop in the scope of a graduate level course with the participation of 12 graduate level industrial design students. The paper first explains the procedure of the design activity. Then, it presents the outcomes under two themes: i) timekeeping related insights: the students' reflections on their timekeeping practices and ideas on how to improve these practices to support wellbeing; ii) pedagogical insights: students' thoughts and instructors' reflections on the online diary-keeping and conducting the workshop remotely. The findings are believed to be beneficial for inspiring designers interested in designing interventions to support better time management practices; and for design educators interested in conducting remote diary study and/or workshop in distance education settings.

Tarım Bilimleri Dergisi, 2020

Popularity of pomegranate fruit has increased in recent years because of its health benefit conte... more Popularity of pomegranate fruit has increased in recent years because of its health benefit content, economic value and medicinal characteristics. Since pomegranate fruit is perishable species, prolonging storage life, keeping fruit quality during storage and marketing period with minimum quality and quantity loss after harvest are essential. Influence of salicylic acid treatments on some quality properties in 'Hicaznar' cultivar fruit were investigated in the current study. After harvest at commercial maturity, fruit were exposed to salicylic acid (SA) treatments. Controls (C1) were untreated. The other groups were dipped into a solution containing 0.01% Tween 20 (C2), 0.01% Tween 20+2 mM SA (SA1), and 0.01% Tween 20+4 mM SA (SA2). Then fruit were stored at 5±1 °C temperature, 85-90% relative humidity for 120 days. Changes in fruit skin and aril color, soluble solids content, titratable acidity, weight loss and chilling injury rate total phenolic content, antioxidant activity were followed at 60 days intervals. Neither SA1 nor SA2 affected total phenolic content and antioxidant activity levels of fruit. But, both treatments helped to maintain C* values in arils and skin, titratable acidity and soluble solids content. Since SA2 treatment significantly reduced chilling injury symptoms during cold storage period of 120 days, it could be considered as promising postharvest technology.

Extended Abstracts of the 2020 CHI Conference on Human Factors in Computing Systems, 2020

Time is a growing topic of interest in HCI. Technological developments and changes in everyday li... more Time is a growing topic of interest in HCI. Technological developments and changes in everyday life routines are creating new perceptions of time that are getting widespread in HCI. While these perceptions expand our current understanding of time, designing for them is an important yet an overlooked challenge. In this work, we investigated five time concepts from HCI literature (right time, clock time, digital time, plastic time, and collective time). We conducted a photography capturing task with four design researchers to understand how they interpret and perceive these time concepts. We then created two design speculations based on their perceptions and interpretations to illustrate how emerging time concepts can inspire new design ideas around representations of time.

Companion Publication of the 2019 on Designing Interactive Systems Conference 2019 Companion, 2019

Water is an essential nutritional source. Its deficiency negatively influences our mental and phy... more Water is an essential nutritional source. Its deficiency negatively influences our mental and physical health. Despite this, people may forget drinking enough water due to the everyday rush in places like office environments. Previously, HCI researchers addressed this problem via developing interactive technologies aimed at motivating regular water intake. However, these technologies heavily rely on giving individual feedback on water intake and self-monitoring as a behavior change strategy. We expanded this existing design space with a new concept: Wwall, a smart water dispenser system which differs from previous examples as it 1) gives collective feedback along with individual feedback via an ambient display, and 2) uses cooperation to motivate regular water intake. In this WIP, we present our design and prototyping process as well as directions for future work

Biomimetics, 2020

This paper presents a soft passive gripper consisting of six fluidic soft bending actuators arran... more This paper presents a soft passive gripper consisting of six fluidic soft bending actuators arranged in a star-shaped manner. The actuators are oriented such that, upon pressurization, they bend against gravity. Gripping is realized by a commercial tape with mushroom-shaped adhesive structures that is glued to the bottom patches of the gripper. In this way, the object is released by peeling away the actuators from the object’s surface. In contrast to active grippers, which require continuous pressurization during gripping and holding, the presented passive gripper only requires energy for the release process. However, due to its working principle, the gripper is restricted to only flat objects or objects with at least one flat surface.

Extended Abstracts of the 2020 CHI Conference on Human Factors in Computing Systems, 2020

What for and how will we design children's technologies in the transhumanism age, and what stance... more What for and how will we design children's technologies in the transhumanism age, and what stance will we take as designers? This paper aims to answer this question with 13 fctional abstracts from sixteen authors of different countries, institutions and disciplines. Transhumanist thinking envisions enhancing human body and mind by blending human biology with technological augmentations. Fundamentally, it seeks to improve the human species, yet the impacts of such movement are unknown and the implications on children's lives and technologies were not explored deeply. In an age, where technologies such as under-skin chips or brain-machine interfaces can clearly be defned as transhumanist, our aim is to reveal probable pitfalls and benefts of those technologies on children's lives by using the power of design fction. Thus, main contribution of this paper is to create diverse presentation of provocative research ideas that will foster the discussion on the transhumanist technologies impacting the lives of children in the future.

Mustafa Kemal Üniversitesi tarım bilimleri dergisi, Apr 19, 2021

Kombu tea is a slightly sweet and acidic beverage that is consumed worldwide but has a low level ... more Kombu tea is a slightly sweet and acidic beverage that is consumed worldwide but has a low level of awareness in our country, resulting from the symbiotic relationship between acetic acid fermentation and alcohol fermentation. Temperature is an important parameter in the production conditions of this drink, which has many health benefits. This study aimed to determine the effect of incubation temperature and fermentation time on physicochemical and microbiological properties of kombucha tea. Methods and Results: In this study, physicochemical and microbiological changes on days 0, 5, 10 and 15 th occurring as a result of incubation in room conditions (15-20°C) and incubator conditions (28°C) were investigated. The pH of the Kombu tea samples produced at room temperature is 3.51-5.39; brix values 8.71-9.57; alcohol content 1.10-3.07%; total amount of phenolic substance 374-364 mg gallic acid L-1 ; antioxidant activity was determined as 80.57-76.58% and density value was 1.037-1.036 g mL-1. The pH of the Kombu tea samples fermented at 28 °C is 3.22-5.39; brix 8.71-10.10; alcohol content 1.10-3.76%; the total amount of phenolic substance 374-430 mg gallic acid L-1 ; antioxidant activity was determined to be 80,57-80,00% and density was 1.037-1.035 g mL-1. A statistically significant difference (p <0.05) in the a* and b* values on the 5 th and 10 th days of different fermentation conditions and the L* and a* values on the 15 th day has been determined. An increase in the number of microorganisms (p <0.05) was detected depending on the fermentation days at both of the Kombu tea produced at different temperatures. According to the fermentation conditions at different temperatures, the increase in the number of yeast-mold was statistically insignificant, while the increase in the 5 th and 10 th days was statistically significant (p <0.05) in terms of the number of bacteria. Conclusions: Instead of standardizing the fermentation temperature and/or duration, the pH value of the product is considered to be an important criterion in determining the fermentation conditions in the production of Kombu tea. Significance and Impact of the Study: In the light of these findings, if standardization is necessary, fermentation time at 28°C is recommended to be 10 days, or at room temperature 15 days.

Companion Publication of the 2019 on Designing Interactive Systems Conference 2019 Companion

Food is an essential nutritional source for all humans, yet tons of food is wasted at an increasi... more Food is an essential nutritional source for all humans, yet tons of food is wasted at an increasing rate each year. Although previous HCI studies examined this issue, most of this work focuses on the domestic context. To the best of our knowledge, no study explored the food waste in the hospitality sector from a design perspective. Addressing this gap, we made observations and interviews in a high-end hotel restaurant kitchen to better understand the sources of food waste in restaurants. From our findings, we envisioned three design speculations which can inspire HCI researchers and practitioners explore this issue further.

Theoretical and Applied Forestry, Sep 1, 2022

Yapay olarak tesis edilen, tohum bahçeleri ve doğal ormanlardan tescillenen tohum meşcereleri; di... more Yapay olarak tesis edilen, tohum bahçeleri ve doğal ormanlardan tescillenen tohum meşcereleri; diğer fonksiyonları yanında ormancılık uygulamalarının en önemli tohum kaynaklarıdır. Ülkemiz ormancılığında bu amaçla 12 tür ve 1443.3 hektarda 185 tohum bahçesi ile 32 tür ve 41880.1 hektarda 318 tohum meşceresi tescillenmiştir. Bu tohum kaynakları içerisinde, doğal yayılış alanının büyüklüğüne bağlı olarak Kızılçam (Pinus brutia Ten.) tohum bahçeleri (78 adet, 663.2 ha) ve tohum meşcereleri (72 adet, 10421.9 ha) bakımından en yüksek paya sahiptir. Tohum kaynaklarının tescil ve tesisine katkı sağlanması amacıyla gerçekleştirilen derleme niteliğindeki bu makalede, Orman Ağaçları ve Tohumları Islah Araştırma Enstitüsü Müdürlüğü tarafından yayımlanan güncel veriler ışığında tohum bahçeleri ve tohum meşcereleri irdelenmiştir.

2020 Medical Technologies Congress (TIPTEKNO), 2020

In this study, the application of Q-routing method to the diffusion MR fiber tractography problem... more In this study, the application of Q-routing method to the diffusion MR fiber tractography problem is proposed. In this way, while benefiting from the advantages of the local streamline methods, to obtain the robustness of global methods by considering the total cost of the path instead of local orientations is aimed. The proposed Q-routing based method, is evaluated on the FiberCup phantom, which is a diffusion phantom mimicing the fiber connections of the human cerebral white matter. The results reveal the potential of the proposed method on the diffusion MR fiber tractography problem.

Lecture Notes in Mechanical Engineering, 2019

Izmir based Information Technology (IT) solution provider develops supply chain management softwa... more Izmir based Information Technology (IT) solution provider develops supply chain management software tools for many customers from fast moving consumer goods sector (FMCG). Customers of the FMCG sector needs to be visited a certain number of times in a given period by sales representatives. The company must decide which customers must be visited in which sequence by each sales representative while obeying visit frequency and time windows requirements. These decisions have significant impact on total cost. For this reason, finding an optimal route for every sales representative for each day of the planning horizon is important. This practically challenging and technically important problem can be described as periodic multiple depot traveling salesman problem with time windows (PMDTSPTW). We propose a novel mathematical model for the optimal solution of this problem. The proposed model minimizes the total distance traveled by sales representatives by deciding which sales representative will visit which customer on which day while following the time windows to collect demand data. The proposed model is applicable to any company from FMCG sector. The solution approach in this study is implemented and tested with real life including coordinates and location data of customers and sales representatives from Turkey’s largest beer distributor. The proposed model is solved using IBM ILOG CPLEX Optimization Studio version 12.8. The results show significant improvement over the current situation. To ensure efficient usage of the proposed approach, a user-friendly decision support system (DSS) is constructed and implemented.

Proceedings of the Design Society, 2021

Taking on the challenge of motivating users to drink water regularly, we designed a smart water b... more Taking on the challenge of motivating users to drink water regularly, we designed a smart water bottle that can track water intake behavior and inform users about this behavior through ambient feedback. We then conducted two studies to explore the bottle's feedback design from the perspective of users and designers. First, we conducted semi-structured interviews with 10 prospective users and found that they would like to receive personalized, precise, gamified and reminding feedback. Second, we conducted a design workshop with 13 professional designers to explore the range of visualizations that can be used to give feedback. Analyzing these visualizations, we identified three reminder types (augmenting, restoring and balancing) and six visualization styles grouped according to three dimensions of ambient displays (representation fidelity, notification level, aesthetic emphasis). In this paper, we first explain our water bottle concept along with existing solutions. Then, we repo...

DS 110: Proceedings of the 23rd International Conference on Engineering and Product Design Education (EPDE 2021), 2021

This paper reports on the procedure and the results of a design activity carried out to reflect o... more This paper reports on the procedure and the results of a design activity carried out to reflect on time and timekeeping practices. The design activity involved a diary study followed by an idea generation workshop in the scope of a graduate level course with the participation of 12 graduate level industrial design students. The paper first explains the procedure of the design activity. Then, it presents the outcomes under two themes: i) timekeeping related insights: the students' reflections on their timekeeping practices and ideas on how to improve these practices to support wellbeing; ii) pedagogical insights: students' thoughts and instructors' reflections on the online diary-keeping and conducting the workshop remotely. The findings are believed to be beneficial for inspiring designers interested in designing interventions to support better time management practices; and for design educators interested in conducting remote diary study and/or workshop in distance education settings.

Tarım Bilimleri Dergisi, 2020

Popularity of pomegranate fruit has increased in recent years because of its health benefit conte... more Popularity of pomegranate fruit has increased in recent years because of its health benefit content, economic value and medicinal characteristics. Since pomegranate fruit is perishable species, prolonging storage life, keeping fruit quality during storage and marketing period with minimum quality and quantity loss after harvest are essential. Influence of salicylic acid treatments on some quality properties in 'Hicaznar' cultivar fruit were investigated in the current study. After harvest at commercial maturity, fruit were exposed to salicylic acid (SA) treatments. Controls (C1) were untreated. The other groups were dipped into a solution containing 0.01% Tween 20 (C2), 0.01% Tween 20+2 mM SA (SA1), and 0.01% Tween 20+4 mM SA (SA2). Then fruit were stored at 5±1 °C temperature, 85-90% relative humidity for 120 days. Changes in fruit skin and aril color, soluble solids content, titratable acidity, weight loss and chilling injury rate total phenolic content, antioxidant activity were followed at 60 days intervals. Neither SA1 nor SA2 affected total phenolic content and antioxidant activity levels of fruit. But, both treatments helped to maintain C* values in arils and skin, titratable acidity and soluble solids content. Since SA2 treatment significantly reduced chilling injury symptoms during cold storage period of 120 days, it could be considered as promising postharvest technology.

Extended Abstracts of the 2020 CHI Conference on Human Factors in Computing Systems, 2020

Time is a growing topic of interest in HCI. Technological developments and changes in everyday li... more Time is a growing topic of interest in HCI. Technological developments and changes in everyday life routines are creating new perceptions of time that are getting widespread in HCI. While these perceptions expand our current understanding of time, designing for them is an important yet an overlooked challenge. In this work, we investigated five time concepts from HCI literature (right time, clock time, digital time, plastic time, and collective time). We conducted a photography capturing task with four design researchers to understand how they interpret and perceive these time concepts. We then created two design speculations based on their perceptions and interpretations to illustrate how emerging time concepts can inspire new design ideas around representations of time.

Companion Publication of the 2019 on Designing Interactive Systems Conference 2019 Companion, 2019

Water is an essential nutritional source. Its deficiency negatively influences our mental and phy... more Water is an essential nutritional source. Its deficiency negatively influences our mental and physical health. Despite this, people may forget drinking enough water due to the everyday rush in places like office environments. Previously, HCI researchers addressed this problem via developing interactive technologies aimed at motivating regular water intake. However, these technologies heavily rely on giving individual feedback on water intake and self-monitoring as a behavior change strategy. We expanded this existing design space with a new concept: Wwall, a smart water dispenser system which differs from previous examples as it 1) gives collective feedback along with individual feedback via an ambient display, and 2) uses cooperation to motivate regular water intake. In this WIP, we present our design and prototyping process as well as directions for future work

Biomimetics, 2020

This paper presents a soft passive gripper consisting of six fluidic soft bending actuators arran... more This paper presents a soft passive gripper consisting of six fluidic soft bending actuators arranged in a star-shaped manner. The actuators are oriented such that, upon pressurization, they bend against gravity. Gripping is realized by a commercial tape with mushroom-shaped adhesive structures that is glued to the bottom patches of the gripper. In this way, the object is released by peeling away the actuators from the object’s surface. In contrast to active grippers, which require continuous pressurization during gripping and holding, the presented passive gripper only requires energy for the release process. However, due to its working principle, the gripper is restricted to only flat objects or objects with at least one flat surface.

Extended Abstracts of the 2020 CHI Conference on Human Factors in Computing Systems, 2020

What for and how will we design children's technologies in the transhumanism age, and what stance... more What for and how will we design children's technologies in the transhumanism age, and what stance will we take as designers? This paper aims to answer this question with 13 fctional abstracts from sixteen authors of different countries, institutions and disciplines. Transhumanist thinking envisions enhancing human body and mind by blending human biology with technological augmentations. Fundamentally, it seeks to improve the human species, yet the impacts of such movement are unknown and the implications on children's lives and technologies were not explored deeply. In an age, where technologies such as under-skin chips or brain-machine interfaces can clearly be defned as transhumanist, our aim is to reveal probable pitfalls and benefts of those technologies on children's lives by using the power of design fction. Thus, main contribution of this paper is to create diverse presentation of provocative research ideas that will foster the discussion on the transhumanist technologies impacting the lives of children in the future.